I see that your iPhone is having trouble with dialing and taking pictures when it's not being touched. I'd like to help out.
Does this happen with the case taken off as well as any screen protectors? Sometimes screen protectors or cases can interfere with the touch display. Also try restarting the iPhone.
If you're still having trouble, the best step would be to determine if the issue is hardware or software related by restoring the iPhone and setting it up as new.
Make sure you have a good backup of your device: How to back up your iPhone, iPad, and iPod touch - Apple Support
When you are ready to restore please follow this article: Restore your iPhone, iPad, or iPod to factory settings - Apple Support
If the issue persists after restoring and setting up as new, the issue will be hardware related and will likely require service at that point. If the issue appears resolved, then restore the backup to the iPhone.
Take care!